The present invention relates to a disk storage device having a rotary recording/reproducing medium, and in particular to a disk storage device capable of improving reliability of recorded data by preventing intentional or accidental destruction of recorded data.
A conventional disk storage is connected to a host device via an interface such as SCSI (Small Computer System Interface). As for the control command of the disk storage device used in this interface, the disk storage device which has received the command cannot determine whether the control command is correct. Therefore, the disk storage device unconditionally executes operation, such as a read or write operation, ordered by the control command.
At the present time, the position occupied by auxiliary storage devices such as disk storage devices in computer systems becomes increasingly important. That is to say, an application program for conducting increasingly complicated and sophisticated processing, and precious user data such as deposit balance are preserved in the disk storage device. At the same time, however, there is an enhanced risk that nonreplaceable precious data preserved in the disk storage device will be destroyed because of a processing error of the application program in the host device, an operation mistake of an operator handling the system, or the existence of a computer virus which is now constituting a social problem.
In order to prevent such a risk of user data destruction, a file management method has been proposed in JP-A-4-287254, for example. According to the file management method, an OS (Operation System) for controlling the host device manages the storage area of the disk storage device in order to prevent abnormal data being written into the disk storage device.